广东徐闻县西部沿岸海域的珊瑚虫纲物种

广东省徐闻县西部沿岸海域分布着珊瑚礁,现生珊瑚虫纲物种较丰富,本文将2004年调查研究的结果,结合文献记录的资料,综合整理,统计有石珊瑚目12科29属56种和5未定种,其它珊瑚虫纲物种有6目15科31种和12未定种．如进一步深入调查研究,还会有本区新的记录．本区石珊瑚目比处于更低纬度的海南岛种属少,但比处于更高纬度的涠洲岛种属多,符合喜热的物种依自然带分布的规律．     

长江江苏段末次盛冰期古河槽特征

选择长江江苏段作为研究河段,根据南京长江三桥、长江大桥、长江四桥、润扬长江大桥、扬中长江大桥、江阴长江大桥、苏通长江大桥7个断面的285个地质勘探钻孔资料及参考文献中的8个钻孔资料,建立了7个长江古河谷地质剖面图。在拟建南京长江四桥附近、扬中长江大桥附近的7个钻孔进行了采样分析,获得了8个14C年代、1个ESR年代数据。通过分析发现,末次盛冰期长江古河槽镇江以上切割到基岩,镇江以下嵌在老河床相沉积层上,河槽在南京下关-栖霞山段形成局部深切;南京段约-63 m以下的河槽为末次盛冰期的古河槽,相对狭窄陡峭,宽深比较小,向下游宽深比逐渐变大,扬中以下形成分叉河道体系;古河槽中自下而上充填了从粗到细的沉积旋回,河床相沉积物向下游逐渐变细。     

基于MODIS时序数据的青海湖流域植被时空变化特征及其与气候因子的关系(英文)

Global warming has led to significant vegetation changes in recent years. It is necessary to investigate the effects of climatic variations(temperature and precipitation) on vegetation changes for a better understanding of acclimation to climatic change. In this paper, we focused on the integration and application of multi-methods and spatial analysis techniques in GIS to study the spatio-temporal variation of vegetation dynamics and to explore the vegetation change mechanism. The correlations between EVI and climate factors at different time scales were calculated for each pixel including monthly, seasonal and annual scales respectively in Qinghai Lake Basin from the year of 2001 to 2012. The primary objectives of this study are to reveal when, where and why the vegetation change so as to support better understanding of terrestrial response to global change as well as the useful information and techniques for wise regional ecosystem management practices. The main conclusions are as follows:(1) Overall vegetation EVI in the region increased 6% during recent 12 years. The EVI value in growing seasons(i.e. spring and summer) exhibited very significant improving trend, accounted for 12.8% and 9.3% respectively. The spatial pattern of EVI showed obvious spatial heterogeneity which was consistent with hydrothermal condition. In general, the vegetation coverage improved in most parts of the area since nearly 78% pixel of the whole basin showed increasing trend, while degraded slightly in a small part of the area only.(2) The EVI change was positively correlated with average temperature and precipitation. Generally speaking, in Qinghai Lake Basin, precipitation was the dominant driving factor for vegetation growth; however, at different time scale its weight to vegetation has differences.(3) Based on geo-statistical analysis, the autumn precipitation has a strong correlation with the next spring EVI values in the whole region. This findings explore the autumn precipitation is an important indicator, and then, limits the plant growth of next spring.     

飞越金星的声与影

飞越金星的声与影 本周早些时候,欧洲航天局(ESA)的Solar Orbiter和BepiColombo航天器进行了历史性的金星飞越,彼此在33小时内分别飞过金星,并在相遇期间捕捉到了独特的图像和数据. ESA/NASA的Solar Orbiter于8月9日飞越金星,距离为7995公里,而ESA/JAXA的BepiCo...     

规天矩地置城乡

正自华夏先民在东方大陆点燃文明的火种,这片古老的黄土地便成为中华儿女生息、繁衍和成长的舞台。每一处都市、城镇、村落、农田、道路和沟渠,都记载着民族的印迹和历史的进程。"画疆兴庶务,地矩囿天规。"如何科学规划、保护与合理开发利用土地,历来是王朝统治者和先贤们思考的重大问题,并由此探索出一条具有东方文化特色的治国之路。     

地生五金铸九鼎

正如果将大地比作母亲,她给予儿女的馈赠无疑是丰厚的。茂密的森林、丰美的草场、肥沃的农田……裹起人类生息繁衍的襁褓。而那隐伏在地层深处的矿藏,更是她最慷慨的礼物。"大地生五金,以利用天下与后世。"矿产资源的开采和利用,开启了华夏文明的新纪元,影响着五千年历史进程,成为推动社会进步与科技发展的重要标志之一。厚土生金:从石块到钢铁"精诚所至,金石为开。"古代本无矿产一词,大多通称"金石"。"金"     

伶仃洋第四纪沉积物的铀钍含量和年龄分析

样品采自珠江口伶仃洋海区的５个钻孔。测量了各样品中之Ｕ，Ｔｈ含量、比值及年龄。结果表明，这５个钻孔基底面上沉积之最老年龄距今超过３６０００ａ。     

运用开放式条件估值方法评估恢复额济纳旗生态系统服务的总经济价值

条件估值方法(CVM)是当前国际上流行的衡量环境物品非利用经济价值的主要方法之一,它通过调查居民针对恢复或改善环境状况变化的支付意愿,从而定量地估计环境状况变化带来的经济效益和损失.针对黑河流域额济纳旗生态系统恶化的现状,以开放式问卷的调查方法设计了500份调查问卷,调查了黑河流域居民恢复额济纳旗生态系统的支付意愿,并采用非参数分析方法对结果进行分析.结果表明,用20年的时间将额济纳旗的生态系统恢复到80年代初的水平,黑河流域总共有93.2%的居民家庭存在支付意愿,有支付意愿家庭的平均支付意愿为每年每户44.9元,同时采用列联表检验的方法辨明了被调查者的年龄、学历、收入、户籍和居住的地理区域等因素对支付意愿的影响.最后在综合不同区域居民支付意愿差异的基础上,采用当前的市场利率将计算结果在时空尺度上加总,得到恢复黑河下游额济纳生态系统的总经济价值的现值为1.224×10⁸元.     

【“漫话土地”之二十九】 天灾地变济苍生

正正如儿女不能选择生己养己的父母,人们同样不能选择繁衍生息的土地。大地就像一位喜怒无常的神祇,带给我们的不仅有风调雨顺的璀璨文明,也有山崩地裂的灾难记忆。从上古传说中的旷世洪水,到世纪之初的汶川地震,天灾地灾从未断绝,考验着人类历史的韧性。而对灾害的预防、治理和赈济,也成为历代治乱兴衰的焦点和治国理政的关键。